This invention relates to an improvement for hand-held paint spray guns, more particularly to sealing a paint inlet to the suction apparatus for such guns.
Referring now to FIGS. 1 and 2, in the past it has been known to use a hand-held spray gun 10 to spray paint drawn either from a cup 12 secured to a flange 14 on the gun or to use an extended suction set 16 to draw paint from a remote container 18. Container 18 can either be a paint can 20 in which the paint is sold, or a bucket 22, as desired by the user. With either the local paint cup 12 or the remote paint container 18, a syphon tube 24 is used to draw paint from the receptacle in which it is located. Syphon tube 24 preferably has a strainer or filter 26 at the suction end thereof to prevent oversize particle solids from entering and clogging gun 10.
The suction apparatus of either syphon tube 24 or suction set 16 of the prior art relied upon frictional interengagement of a tapered end of the suction apparatus mating with a tapered bore in a paint inlet of the spray gun. Because gun 10 uses a vibratory motor to atomize paint, the suction apparatus was subject to loosening and detachment from gun 10. Furthermore, when the suction apparatus was not positively engaged to the inlet port of gun 10 initially, the gun was unable to draw paint through the suction apparatus because of air linkage between the inlet port and the suction apparatus, thus preventing drawing paint into the gun for spraying.
Unanticipated separation of the extended suction set 16 from the gun 10 while paint was flowing would result typically in paint spillage, requiring additional and unanticipated clean-up.
The present invention overcomes shortcomings of the prior art by providing an inlet seal to provide apparatus and method for positive engagement of the suction apparatus with the paint inlet port to both initially make a positive engagement and to maintain such engagement throughout the spraying operation.